Pastels are ghosts that show alot of pink. The term is most often associated with ghost motleys, but, IMO, could be used to describe any ghost regardless of pattern. My adult male ghost motley was sold to me as a pastel motley, but his coloration isn't anywhere as pink as my normal patterned adult ghost female. A high percentage of their offspring show alot of pink as well, but whether it came from "Mom" &/or "Dad", I can't be sure.
I did breed "Dad" to his oldest daughter (who is not very pink) this year and the results were intersting...the normal patterned hatchlings tended to be fairly dark ghosts and didn't show much inclination towards becoming pink. However, all 4 ghost motleys were much lighter in color and will probably become definate pastels. I only kept one of these and, when I get a decent digital camera, will post some pics of her.
In the meantime, my avatar is of my pastel ghost het motley male and below is "Mom" (her real name is Why and came from the "Y" pattern on her head. OK, I admit it, I was in a very strange mood when I named her.) and the oldest daughter (Fantasia - the smaller one). The pic was taken in the late spring of 2002.